On 02/02/2011 04:52 PM, Jan Kiszka wrote:
On 2011-02-02 15:43, Jan Kiszka wrote:
> On 2011-02-02 15:35, Avi Kivity wrote:
>> On 02/02/2011 04:30 PM, Jan Kiszka wrote:
>>> On 2011-02-02 14:05, Avi Kivity wrote:
>>>> On 02/02/2011 02:50 PM, Jan Kiszka wrote:
>>>>>>>
>>>>>> Opps, -smp 1. With -smp 2 it boot almost completely and then hangs.
>>>>>
>>>>> Ah, good (or not good). With Windows 2003 Server, I actually get a Blue
>>>>> Screen (Stop 0x000000b8).
>>>>
>>>> Userspace APIC is broken since it may run with an outdated cr8, does
>>>> reverting 27a4f7976d5 help?
>>>
>>> Can you elaborate on what is broken? The way hw/apic.c maintains the
>>> tpr? Would it make sense to compare this against the in-kernel model? Or
>>> do you mean something else?
>>
>> The problem, IIRC, was that we look up the TPR but it may already have
>> been changed by the running vcpu. Not 100% sure.
>>
>> If that is indeed the problem then the fix would be to process the APIC
>> in vcpu context (which is what the kernel does - we set a bit in the IRR
>> and all further processing is synchronous).
>
> You mean: user space changes the tpr value while the vcpu is in KVM_RUN,
> then we return from the kernel and overwrite the tpr in the apic with
> the vcpu's view, right?
Hmm, probably rather that there is a discrepancy between tpr and irr.
The latter is changed asynchronously /wrt to the vcpu, the former /wrt
the user space device model.
And yet, both are synchronized via qemu_mutex. So we're still missing
something in this picture.
Run apic_set_irq on the vcpu?
static void apic_set_irq(APICState *s, int vector_num, int trigger_mode)
{
apic_irq_delivered += !get_bit(s->irr, vector_num);
trace_apic_set_irq(apic_irq_delivered);
set_bit(s->irr, vector_num);
This is even more async with kernel irqchip
if (trigger_mode)
set_bit(s->tmr, vector_num);
else
reset_bit(s->tmr, vector_num);
This is protected by qemu_mutex
apic_update_irq(s);
This will be run the next time the vcpu exits, via apic_get_interrupt().
}
Did you check whether reverting that commit helps?
--
error compiling committee.c: too many arguments to function
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